Electronic eneigy transfer

Direct intermolecular electronic-eneigy transfer was first observed in this way in the gas phase, in a mixture of mercury and thallium vapours (G. Cario and J. Franck, Z Physik 17 (1923) 202). An instance of the phenomenon in solution was reported by Th. FSrster in Aim. Phys. 1 (1948) 55 Z Elektrochem. 53 (1949) 93. It is often called sensitised fluorescence . It is a case of non-radiative energy transfer, by contrast with radiative transfer in which a photon is emitted by one molecule and absorbed by another (A - A + /iv )n> + B -> B). The latter type of transfer gives little information on molecular interactions indeed the A and B molecules need not even be in the same vessel. It is of great practical importance, however, notably in photosynthesis, which makes use of photons emitted from the sun (Section 4.3.6.1). 

Bodunov EN, Berberan-Santos MN, Martinho IMG (2001) Electronic eneigy transfer in linear polymers randomly labelled with chromophores. Chem Phys 274(2—3) 243—253. doi 10.1016/s0301-0104(01)00545-6... 

N. Lokan, M. N. Paddon-Row, T. A. Smith, M La Rosa, K P. Ghiggino, S. Speiser, Highly Efficient Through-Bond-Mediated Electronic Excitation Eneigy Transfer Taking Place Over 12 A , J. Am Chem Soc 1999,121,2917-2918. 

Electronic Structure and Eneigy Transfer in Solid a-Sexithienyl... 

Fig. 10.3 The experimental results of NO vibration on metal or Li are shown. Loss of L5 eV within 100 fs on Au implies an electron-mediated process and almost no vibrational relaxation on the LiF insulating surface [23], (a) Plot of vibrational energy loss to an insulator and (b) metal surface for collisions of highly vibrationally excited NO. When NO is prepared in v = 12, eneigy transfer to LiF is approximately vibrationally elastic however, when NO is prepared in v= 15, collisions with Au(l 11) transfer an average of 1.3 eV to the surface (Reprinted with permission from ref [23]. 2000 AAAS.)...

H. Imahori, K Hagiwara, T. Akiyama, M. Aoki, S. Tani-guchL T. Okada, M Shirakawa, Y. Sakata, The Small Reorganization Eneigy of CHI in Electron Transfer , Chem. Phys. Lett. 1996,263,545-550. 

Taken as a group, PV cells comprise solid-state devices in which photons of light collide with atoms and transfer their eneigy to electrons. These electrons flow into wires that are connected to the cells, thereby providing current to electrical loads. 

Spectral Sensitization. Photographic silver halide emulsions are active with light only up to about 500 nm. However, their sensitivity can be extended within the whole visible and near-ir spectral region up to about 1200—1300 nm. This is reached by the addition of deeply colored dyes that transfer excited electrons or excitation eneigy to the silver halide. 

Radiation Damage. It has been known for many years that bombardment of a crystal with eneigetic (keV to MeV) heavy ions produces regions of lattice disorder. An implanted ion entering a solid with an initial kinetic energy of 100 keV comes to rest in the time scale of about 10 13 due to both electronic and nuclear collisions. As an ion slows down and comes to rest in a crystal, it makes a number of collisions with the lattice atoms. In these collisions, sufficient eneigy may be transferred from the ion to displace an atom from its lattice site. Lattice atoms which are displaced by an incident ion are called primary knock-on atoms (PKA). A PKA can in turn displace other atoms, secondary knock-ons, etc. This process creates a cascade of atomic collisions and is collectively referred to as the collision, or displacement, cascade. The disorder can be directly observed by techniques sensitive to lattice structure, such as electron-transmission microscopy, MeV-partide channeling, and electron diffraction. 

The x-ray photon is completely absorbed. No x-ray photon leaves the object. All of the eneigy of the x-ray photon is transferred to the electrons... 

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